1. Field of Invention
This invention is related to a printed circuit board (PCB) and more particularly to a PCB with a supporting woven fabric to reduce the quantity of bumps formed on the supporting woven fabric.
2. Description of Related Art
A supporting board in a printed circuit board (PCB) used for upholding objects thereon is traditionally made by a piece of paper enveloped in resin. Nowadays, Referring to FIG. 1 a plain schematic diagram of a conventional fiberglass woven fabric, the supporting board of the PCB can be a fiberglass weaving work 500. The fiberglass weaving work 500 is woven by a plurality of fiberglass strands with longitudinal direction (called warp 510 as follows) interlaced through a plurality of fiberglass strands with latitudinal direction (called weft 520 as follows) wherein the warps 510 in an order of odd numbers are interlaced through every weft 520 by a rule of passing under one weft 520 first and then crossing over next one weft 520, and the warps 510 in an order of even numbers are interlaced through every weft 520 by a rule of crossing over one weft 520 first and then passing under next one weft 520, thus the fiberglass weaving work 500 presents the so-called “PLAIN WEAVING” in one leaf (i.e. the action of crossing) and one fly (i.e. the action of crossing) in the textile weaving jargon.
However, after the fiberglass weaving work 500 is processed to be a PCB, thousands of conductive traces are plated on the PCB and because every warp 510 that crosses over the weft 520 will respectively forms a bump upwardly on the fiberglass weaving work 500, some of those conductive traces will unavoidably be arranged to lie on the bumps. The bumps may weaken the power and slow the speed of transmitting signals through the conductive trace thereon to provide bad performance. Therefore, it is crucial to provide a new PCB supporting woven fabric to solve the problems for the Industry.